aokerson



(No Model.)

0. H. AOKERSON SUPPORT FOR CENTERS FOR MASONRYARGHES. Nb. 317,072.

Patented May 5, 1885.

UNITED STATES PATENT OFFICE.

CHARLES H. ACKERSON, OF SAN FRANCISCO, CALIFORNIA.

SUPPORT FOR CENTERS FOR MASONRY ARCHESL SPECIFICATION forming part of Letters Patent No. 317,072, dated May 5, 1885.

Application filed January 5, 1885. (No model.)

To aZZ whom it may concern: 7 Be it known that 1, CHARLES H. Acnnnson, of the city and county of San Francisco, State of California, have invented an Improvement 5 in a Support for Centers for Masonry Arches; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to a means for supporting the temporary centerings upon which masonry arches are built; and it consists of links which are fitted to hang from the edges of the girders between which the arches are built, and to support the ends of the temporary arches so that they are suspended from the girders, as will be more fully described by reference to the accompanying drawings, in which- Figure 1 is a perspective view showing a portion of two arches with temporary centerings and supporting-links. Fig. 2 is atransverse section showing a completed arch and the links knocked away so as to allow the temporary centering to be removed.

In building arches it is necessary to first construct temporary wooden frames or centerings upon which the arches are constructed. These centerings are usually supported by timbers directly from the ground or surface below, which in the case of basements must be sufficiently leveled for that purpose. This consumes considerable time and material, and often causes damage to'the arches or girders when the centers are removed, because the weight of the arch, which has previously been supported upon the timbers, is brought suddenly upon the girders by removal of this support, which causes the gird ers to settle.

In my invention, A A are links of iron bent so as to form a bight at their central portion, and having ends bent at right angles, as shown at B, so that they may be hooked over the edges of the girders C.

D D are the wooden center arches, having 5 the strips E fastened to them, so as to form supports of the desired length and proper curve, and upon which the masonry arches F are constructed. The ends of the wooden arch-pieces D are inserted into the loops formed by the links A, and these are supported by the bent ends B directly from the flanges of the girders, as shown.

The arches F are built in the usual way, springing from the flanges of the girders upon which they are supported, and when the key- 5 5 stone has been put in and the arch is complete the temporary centering is easily removed by knocking the links A away from the ends of the arch-pieces D, as shown in Fig. 2, when the wooden supports will be allowed to fall away, leaving the masonry of the arch entirely supported by the girders. By this construction I avoid the use of any struts or timbers from below; the weight of the arch is gradually brought upon the girders as it is 6 5 built, and any settling that may occur will take place gradually. When the temporary centers are removed, no sudden strain is brought upon the girders, and the weight of the arch continues to be supported by them as when it was being built. By this construction I am enabled to build arches with much greater rapidity, with less expenditure of time and material, and the resulting structure is more complete and satisfactory. 7 5

Having thus described my invention, what I claim as new, and desire tOsecure-by Letters Patent, is

1. The links A, adapted to receive the ends of the temporary arch-pieces of masonry ce-n- 8o terings, and having their ends bent so as to hook upon and be supported by the flanges of the girders between which the arches are built, substantially as herein described.

2. Parallel girders between which masonry arches are built, and temporary centerings for the support of said arches while in process of construction, in combination with links by which the temporary arches are supported directly from the flanges of the girders, substano tially as herein described.

In witness I have hereunto set my hand.

CHARLES H. ACKERSON. Witnesses:

S. H. Noonsn, H. 0. LEE. 

